Complete the following by using a suitable question tag: I am working…

The correct answer is Option (3) → aren't I

Question tag after "I am":

• A positive statement takes a negative tag, using the same auxiliary and the subject pronoun.
• "Amn't I" is not used in standard English; the negative tag for "I am" is "aren't I?"
• Complete sentence: I am working hard on this assignment, aren't I?
  Example: I am late again, aren't I?

Why the Other Options are Incorrect?

Option 1: won't I — Incorrect. "Won't" goes with a statement using will ("I will help, won't I?"); the auxiliary here is "am".

Option 2: will you — Incorrect. The tag must repeat the subject "I", and it must be negative.

Option 4: can you — Incorrect. Both the auxiliary ("can") and the pronoun ("you") are wrong for "I am".